class Solution(object):
    def arraysIntersection(self, arr1, arr2, arr3):
        """
        :type arr1: List[int]
        :type arr2: List[int]
        :type arr3: List[int]
        :rtype: List[int]
        """
        set1 = set(arr1)
        set2 = set(arr2)
        set3 = set(arr3)
        out = list(set1 & set2 & set3)
        out.sort()
        return out
